How do you encourage others in faith?

     One of the things that I struggle with in my faith is the relationship that I have with other Christians.  There are so many verses in the Bible and sometimes I wonder how they are to be implemented or interpreted.  Galatians 6:2 says "Bear ye one another's burdens and so fulfill the law of Christ.  This tells me that I should be carrying others burdens and lifting them up to Christ.  What does that mean when you see loved ones that are making choices that are sinful or just not good choices.  Should you say something? 
     Then you think about Matthew 18:7 which states, "Woe to the world because of [its] stumbling blocks! For it is inevitable that stumbling blocks come; but woe to that man through whom the stumbling block comes! "  What if you become a stumbling block  because of something that you say.  But, then in Ephesians 4, verse 15 says, "¹⁵ Instead, speaking the truth in love, we will grow to become in every respect the mature body of him who is the head, that is, Christ."  So what are we to do? 
      I have been on the giving end and the receiving end of this struggle.  In high school, I spoke to a friend about smoking pot.  I prayed with her over the phone and asked her to consider her behavior.  Nothing changed for several years.  But, I knew that what I had done was out of love and I still speak to her today.  I don't think my words changed anything.  I think she was on her own journey.  She modified her behavior when she wanted to.  I also had a friend speak to me about the intimacy involved in my relationship with my now husband.  At the time, I was a little upset.  But, I have not held that against her nor has it impacted our relationship.  We will be going to the zoo with our children tomorrow.  However, I know there are times when it can end relationships. 
     The thing that concerns me is that I think we enter into conversations with others in a fast and sometimes unthoughtful manner.  When we speak the truth in love, if that becomes necessary, I think that God should be called upon to be the center of the conversation.  Ask him to give you the words to speak.  Then, and only then, do I think that there is a possibility to make it through a difficult discussion without disastrous results.  Now, I know that I pop off at times.  But, I have also found that when that happens, hurt feelings result.  And God calls us to build each other up and not tear each other down.  I think the Christian community has to be careful that we don't tear each other down over small theological differences that Jesus would probably laugh about.